I wonder if a fresnel lens from, i.e., an old rear-projection television could be integrated into this somehow... I dismantled and trashed an old television recently and kept some of the choice electronics, the mirror and the lenses (one fresnel and one lenticular) and I have discovered that the fresnel lens, even being only a thin sheet of plastic with a ring pattern, can focus sunlight exceptionally well. I got a lovely spot of deadly burning light about the size of a tennis ball and it did light a cigarette butt...

As for the television, taking it out of the house in one piece would have left our house in several. We punctured the walls in a couple of places bringing it in and that had to be repaired. That television was far too big. :)

Eris

My brother and I made a solar oven at ages 9 and 11 for a Boy Scout project. 1962. Seared a hamburger patty in nothing flat, using curved cardboard and aluminum foil.

We wanted to have another go at it with a fresnel lens that could be bought out of a scientific equipment catalogue but Mother put the kabosh on it. Said our eyes were glittering a little too much.

BlackFlag55

[solarcookers.org] links to an organization that distributes solar cookers all over the world to help reduce the use of wood and coal.

They have kits, plans, and ready-to-go solar cookers.

richardchaven

We used to do that in Boy Scouts years ago. It works, but is slow and requires good weather and hot sun. ;-)

Speedmaster

What was old is new again. They just repackaged it as "eco".

QuinnTheEskimo

I'd imagine if you had the location right this could replace a BBQ?

Myles

@Myles: No, not really. The solar cooker basically only provides direct heat. It's not helpful in cooking situations that require radiant, indirect or convection cooking which is what typically happens on a BBQ grill, especially if you use the two-level technique.

The solar cooking technique is mostly useful for small pieces of food. Since the heat is concentrated on a small spot, it's no good for roasts.

Deprong Mori

Parabolic cookers are pretty dangerous. As they focus light to one point it is very easy to damage your eyes when using one. A Solar Oven is a much better idea, and only a piece of glass, cardboard, and tin foil is needed.

In either case always wear sunglasses when using one!

nneuropolitique

Gotta say something here: I have been cooking with the sun for years and the remarks are basically accurate--yes, were eye protection when you are observing the focal point. Scientific catalog Edmund Scientific has solar sunglasses for lees than two bucks. To cook soups and roasts and whole chickens simply arrange a shelf at the focal point that can hold a lidded black pot. Come outside about every fifteen minutes to re track the sun if you do not use an auto tracker. Not to sound contrary, folks, but the sun can easily cook a delicious meal for four people. Yum-Yum.

fishhead455

this is fantastic! a girl i know lives in a sustainable living home and she says food cooked in this manner is delicious!

jeitobob

I bought a Solar CooKit a few weeks ago, and since then have baked bread and prepared a few meals in it. I have been using a large black pot, into which I can put pyrex dishes containing the food items, and all of this goes into a plastic oven bag, not my favorite idea but it seems to address Deprong Mori's concerns.

I've posted about some of my results at my food blog.

wtb